Aggressive wastewater sludges conditioning with polyelectrolytes

Abstract

For the purpose of ferrous metallurgy enterprises negative impact reduction on human health and environment an extremely relevant task is aggressive wastewater treatment facilities implementation at these enterprises, including formed sludge conditioning and mechanical dewatering equipment. Researches results of one of the Ural steel plant operating treatment facilities sludge flocculant processing are reflected in the article. Sludges of two types were investigated: sludge which is formed in clarifiers during pickling solution neutralization; sludge which is formed in clarifiers during rinsing water neutralization. Herewith for neutralization calcium hydroxide was used. During the work non-ionic, cationic and anion flocculants efficiency was estimated. As flocculant processing efficiency criterion the shortest time of water capillary suction from flocculant processed sludge was accepted. It was defined with use of the capillary suction time (CST) device and Whatman 17 chr paper. It is established that for spent pickling solutions neutralization sludge conditioning non-ionic flocculant Praestol 2500 dose of 4 g/kg dry solids is effective and for rinsing water neutralization sludge - anionic flocculant Praestol 2540 dose of 2 g/kg dry solids.